The Specific Aims of this study are to explore changes in cognitive processes associated with acute stress. The proposed study extends previous research suggesting that acute stress is associated with (a) a shift in cognitive processes, favoring enhanced reaction time and short-term memory at the expense of long-term memory consolidation, and (b) enhanced automatic cognitive processes and habitual responses. These Specific Aims are intended to elucidate the cognitive processes that may be associated with relapse (Specific Aim 1) and successful recovery (Specific Aim 2) from drug addiction. Specific Aim 1. Acute stress may facilitate the automatic cognitive processes that support habitual responses. Experiment 1 tests the hypothesis that acute stress is associated with enhanced automatic cognitive processes and reduced effortful cognitive processes. Using a well-established stress-induction paradigm (and a control condition) participants will complete cognitive tasks that allow dissociation of the influences of automatic and conscious (effortful) processes on cued recall of verbal material. This experiment will examine psychological, autonomic, and neuroendocrine indicators of acute stress and their relations with measures of automatic and effortful processes. Specific Aim 2. Previous research has established that acute stress is associated with enhanced reaction time and short-term memory at the expense of long-term memory consolidation. A state of relaxation, in contrast to acute stress, may be associated with a mode of cognitive processing that supports effortful, long-term, and declarative processes. Experiment 2 tests the hypothesis that an acute state of relaxation using a stress-reduction technique will be associated with enhanced long-term memory consolidation and reduced reaction speed and short-term memory' capacity.